Like all of these traffic systems, it relies on data from the Trafficmaster, the Highways Agency and Police to keep it up to date. I also believe that the UK TMC system only updates about every 15 minutes - which on a motorway is too long. There may of course be a bandwidth limit on the TMC data rate that Classic FM can carry - any higher and you would begin to hear it interlaced in the music data.

I too have frequently found that delays and hold ups are no longer there, whilst others are not reported. How often have we sat in stationary traffic without any warning only to have 'Caution - Stationary Traffic' announced by "Nagging Nora" 5 minutes after we stopped? There are of course large parts of the UK with absolutely no sensors installed (blue boxes in short masts or on bridges) so we'll only ever know about those if the Authorities report them to the TMC centre.

Radio bulletins are frequently just as bad, even though in some cases the traffic team are sat close by or next to the Police team in the same control room!!

As you say it is the 'human' element and until that is taken out of the loop and the interface with all of the thousands of traffic flow sensors now installed in the UK is automated we will go on being fooled by inaccurate, late or missing TMC and traffic bulletin announcements.

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